Impression roll support and control means



May 5, 1964 L. H. HASKIN, JR

IMPRESSION ROLL SUPPORT AND CONTROL MEANS 4 Sheets-Sheet 1 I Filed Jan. 8, 1962 INVENTOR. LAWRENCE 7H. 'HASKIN JR.

May 5, 1964 L. H. HASKIN, JR. 7 IMPRESSION ROLL SUPPORT AND CONTROL MEANS 4 Sheets-Sheet 2 Filed Jan. 8, 1962 a W I. H I I m 1V? 4 paw 1 8 88 9 9 w W u w v a 2 A m m 13 a m N, e a m m m w 7 2 |||L| |r 9 u f I LE 6 6W 1 u i 2f Mn NIH INVENTOR. LAWRENCE H. HASKIN JR.

y 5, 1964 L. H. HASKIN, JR 3,131,631

IMFRESSION ROLL SUPPORT AND CONTROL MEANS Filed Jan. 8, 1962 4 Sheets-Sheet 3 LAWRENCE H. HASKIN JR.

May 5, 1964 1.. H. HASKIN, JR 3,131,631

IMPRESSION ROLL SUPPORT AND CONTROL MEANS Filed Jan'. 8, 1962 4 Sheets-Sheet 4 INVENTOR. LAWRENCE H. HASKIN JR.

United tes This invention relates to printing presses.

More particularly, the invention is concerned with improved support and control means for impression rollers of printing presses and has particular utility in multicolor rotogravure presses and flexographic printing presses. The invention may also be employed in other known types of presses including single unit rotary presses and the like employing an impression roller.

An object of the invention is to provide simplified support and adjustment means for the impression rollers of a multi-color printing press, enabling the contact or printing pressure between the impression rollers and printing cylinders to be varied and accurately maintained and also allowing the impression rollers of the press to be raised and lowered in unison or individually relative to the printing cylinders.

Another important object is to provide fluid pressure operated means for raising and lowering the impression rollers and maintaining them and their carrier brackets in firm contact with positive stop means during the printing operation and while the desirable contact pressure is maintained upon the web passing between the impression rollers and printing cylinders.

Another object of the invention is to provide upon the impression roller carrier bracket improved highly accurate adjusting means for the impression roller so that the latter may be readily adjusted into parallelism with the printing cylinder, and also facilitating accurate adjustment and wide variation of the contact or printing pressure between the impression roller and printing cylinder.

Another object is to provide in mechanism of the above-mentioned character novel and simplified spring means working in conjunction with fluid pressure control means to quickly elevate or separate the impression rollers from the printing cylinders as when the press is stopped or at other desired times.

Still another object is to provide fluid pressure control means for raising and lowering all of the impression rollers in unison or separately and independently as preferred.

Another object is to provide upon each impression roller carrier bracket an adjustable web tensioning roll which moves with the pivoted carrier bracket to maintain the web taut in all adjusted positions of the carrier bracket and impression roller.

Further and general objects of the invention are to provide printing mechanism of the mentioned character having simplicity of design and construction, efiicieney of operation, ease of maintenance and economy of manufacture.

The novel features that are considered characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organization and its method of operation, together with additional objects and advantages thereof, will best be understood from the following description of a specific embodiment when read in connection with the accompanying drawings, wherein like reference characters indicate like parts throughout the several figures and in which:

FIGURE 1 is a fragmentary vertical section taken substantially on line 11 of FIGURE 2 just inwardly of one atet of the frame sides of the press and showing substantially one printing unit of the multi-unit rotogravure press;

FIGURE 2 is a fragmentary cross section taken on line 2-2 of FIGURE 1;

FIGURE 3 is a fragmentary horizontal cross section taken on line 33 of FIGURE 1;

FIGURE 4 is an enlarged vertical section taken on line 4-4 of FIGURE 3;

FIGURE 5 is a fragmentary vertical section taken on line 55 of FIGURE 1;

FIGURE 6 is a schematic view or diagram of the fluid pressure control system for the several impression rollers of the printing press, and

FIGURE 7 is a diagrammatic View of a single printing unit similar to FIGURE 1 and showing the relative positions of parts when the impression roller is elevated from the printing cylinder.

Referring to the drawings in detail, the multi-unit press comprises spaced upstanding frame sides 10 and 11 upon and between which are mounted the individual printing units of the multi-color rotogravure press, it being understood that the press may embody any practical number of such printing units. FIGURES l5 and 7 of the drawings illustrate the details of a single printing unit according to the invention and the construe tions shown in these figures are identical to the constructions of all of the other printing units of the press. FIG- URE 6 shows schematically the multiple units of the press and the fluid pressure control and operating means for the several impression rollers and associated parts.

With continued reference to FIGURES 1-5 and 7, each printing unit embodies a lower printing cylinder 12 suit ably journaled for rotation upon and between the frame sides 10 and 11 in a conventional manner. Above the printing cylinder 12 and between the frame sides 10 and 11 is arranged a vertically swingable impression roller assembly 13 for each printing unit of the press. Each assembly 13 includes a generally L-shaped rigid carrier bracket 14 having an upper horizontal portion 15 and vertical end plates 16 rigid with the horizontal portion 15 of the carrier bracket. The vertical end plates 16 include at corresponding sides thereof depending leg portions 17 provided at their lower extremities with integral sleeves 18, pivotally mounted upon horizontally coaxial pins 19 rigid with the frame sides 10 and 11 and whose axis is parallel to the axis of the printing cylinder 12 and spaced from one side of the printing cylinder, FIGURE 1, and somewhat above the axis of the latter. The carrier bracket 14 and all parts mounted thereon constituting the assembly 13 is rockable vertically upon the axis of the fixed pins 19 as will be further described.

The assembly 13 further comprises an impression roller 20 for coaction with the printing cylinder 12 to effect the printing of the web 21 with a single color at a given unit of the multi-unit press. With reference to FIGURE 5, the impression roller 20 is journaled for free rotation on a through shaft 22 through the medium of end frictionless bearings 23 or the like. End reduced extensions 24 of the through shaft 22 are held within bearings 25, secured by bolt means 26, FIGURE 1, to a crosshead 27, rigid with a vertical screw shaft 40 threaded in an upstanding tubular internally screw-threaded shaft 28 journaled for rotation within a vertical opening 29 in the top portion 15 of carrier bracket 14. Each reduced shaft extension 24 is secured against rotation in the adjacent bearing 25 by a key 30. The construction above-described is identical in each end mounting of the impression roller 26).

The through shaft 22 of each impression roller 20 is 0 held against axial displacement by suitable nuts 31 and washers 32 at the opposite ends thereof bearing upon the outer sides of the bearings 25. Each tubular shaft 28 is provided at its lower end with a flange 33 bearing upon the bottom of carrier bracket portion 15, FIGURE 5. Mounted upon each tubular shaft 28 above the bracket portion and secured thereto for rotation therewith by a key 34 is a worm gear 35 having its lower hub portion 36 bearing upon a washer 37, in turn resting upon the top of bracket portion 15 and also engaging a shoulder 38 of tubular shaft 28 as shown in FIGURE 5. The tubular shaft 28 is thus held against axial or vertical movement but is free to turn within the opening 29. A nut 39 is secured to the upper end of each tubular shaft 28 and bears upon the top of the worm gear 35 to hold the latter in contact with the washer 37.

The vertical screw shaft 40 is raised or lowered when the tubular shaft 28 is rotated in one direction or the other under influence of the worm gear 35. The lower end of each screw shaft 40 is provided with an extension 41 rigidly secured by welding or the like to the crosshead 27. Each crosshead 27 is provided upon its outer side with a vertical upstanding slide 42 rigidly secured thereto by screw means 43 and being vertically shiftable in a vertical guideway 44 fonmed through the adjacent end plate 16 of the carrier bracket 14. The slides 42 serve to maintain the bearings 25 and/ or the opposite ends 24 of the impression roller through shaft 22 in alignment during replacement of the impression roller when necessary, and the slides 42 also help to relieve the shaft ends 24 of torsional strains from the screw shafts 49 during the adjusting operations.

With continued reference to the drawings, pairs of bearing brackets 45 and 4-5 are rigidly mounted upon the carrier bracket portion 15 and spaced from one side of the axis of the impression roller 20, FIGURE 1. Journaled for rotation upon the bearing brackets 45, FIGURE 3, is a horizontal manually operable adjusting shaft 46 having a first worm pinion 47 secured thereto for rotation therewith by a key 48. The worm pinion 47 is engaged between the bearing brackets 45 and held thereby against axial movement. The worm pinion 47 is in continuous mesh with the adjacent worm gear 35 above one end of the impression roller shaft. A stop collar 49 secured to the adjusting shaft 46 by a set screw 50 bears against the adjacent bearing bracket 45 as shown in FIGURE 3. The shaft 46 extends parallel to the axis of the impression roller 20 and includes a reduced portion 51 surrounded rotatably by a tubular shaft 52 journaled for rotation within the bearing brackets 45 and carrying a second worm pinion 53 secured thereto for rotation therewith by a key 54. The worm pinion 53 has one end engaging one of the bearing brackets 45' and its other end engaging a flange 55 on the tubular shaft 52, FIGURE 3. The worm pinion 53 is in constant mesh with the other worm gear 35 adjacent the other end of the impression roller shaft.

Outwardly of the main frame side 10 a relatively large hand wheel 56 is secured to the tubular shaft 52 by a key 57 to turn the tubular shaft alone or together with the shaft 46. A second and smaller hand wheel 58 is mounted upon a reduced extremity 59 of the shaft 46 and secured thereto by a key 60 for turning the shaft 46. The hand wheel 58 is shiftable axially upon the shaft portion 59 against the force of a compression spring 61 having its ends bearing against the back of the hand wheel 58 and a head 62 on the extreme end of the shaft portion 59. The hand wheel 58 has an axially shiftable male splined clutch head 63 rigid therewith and engageable with a female splined clutch ring 64 rigidly secured to the hub 65 of hand wheel 56 by screws 67.

The arrangement is such that when the parts are coupled in the rnanner shown in FIGURE 3, the shaft 46 and the tubular shaft 52 may be turned in unison by the larger hand wheel 56 for turning both worm pinions 4'7 and 53 and both worm gears 35 in unison. By virtue of this arrangement, both shaft ends 24 of the impression roller 26 may be raised and lowered in unison to elevate or lower the impression roller 20 relative to the printing cylinder 12 and thereby regulate the contact or printing pressure through relatively wide limits as is necessary for printing webs of different material and requiring varying printing pressures. When the worm gears 35 are thus turned in unison, the two screw shafts 40 will be raised or lowered in unison along with the crossheads 27, slides 42 and bearings 25, as should now be obvious.

When the smaller hand wheel 58 is retracted against the spring 61 and turned slightly to uncouple the clutch parts 63 and 64, the shaft 46 and its worm pinion 47 and the tubular shaft 52 and its worm pinion 53 may be rotated independently by the hand Wheels 58 and 56 respectively to independently raise or lower the screw shafts 40 and the respective ends of the impression roller 20. Accordingly, when the worm pinions 47 and 53 are independently turned as above-described, the opposite ends of the impression roller 20 may be raised and lowered slightly as required to produce true parallelism and a true line of contact between the impression roller and the printing cylinder. The contact pressure between the impression roller and printing cylinder may be regulated by turning both of the worm pinions 47 and 53 and both worm gears 35 in unison as previously stated. Therefore, the adjustment means for the impression roller 20 is highly accurate and allows for a very fine adjustment of the impression roller alignment and the degree of printing pressure may be varied to meet the needs of the particular type of work. The entire adjustment means above-described for the impression roller 20 is bodily mounted upon the carrier bracket 14 along with the impression roller.

Likewise bodily mounted upon each carrier bracket 14 near and inwardly of its ends plates 16 is a pair of upstanding support brackets 68 for a web tensioning roll 69 spaced above the impression roller 20 and spaced laterally therefrom substantially directly above the pins 19, FIG- URE 1. The support brackets 68 are rigidly secured by bolt means 70 to one vertical edge of the horizontal carrier bracket portion 15, FIGURE 1. The web tensioning roll 69 has suitable frictionless bearings 71 rendering the roll freely rotatable upon a through shaft 72, the ends of which are carried by laterally adjustable internally screw-threaded support sleeves 73 having screw-threaded engagement with and supported by transversely extending horizontal adjusting screws 74 journaled for rotation upon the brackets 68 as shown. The sleeves 73 are connected with transverse pins 75 rigid with the shaft 72, whereby either or both ends of the web tensioning roll 69 may be adjusted laterally toward and from the axis of the impression roller 20 upon manipulation of the screws 74. This assures proper parallelism of the roll 69 with the impression roller 20 and proper tensioning of the web 21 in all adjusted positions of the rockable impression roller assembly 13. It is emphasized here that the adjustable tensioning roll 69 is carried bodily by the carrier bracket 14 and forms an integral part of the rockable assembly 13. Consequently, when the impression roller 20 is elevated from the printing cylinder 12 in a manner to be described and as shown diagrammatically in FIGURE 7, the web 21 remains taut and does not have its tension changed because the tensioning roll 69 moves through the same are about the axis of the cross shaft 19 as does the impression roller 20.

Additional conventional rolls 76 and 77 engage the web 21 well above the assembly 13, FIGURES 1 and 7, and these latter rolls are journaled for rotation on parallel horizontal shafts which may be fixedly mounted upon and between the frame sides 10 and 11. The rolls 76 and 77 have their axes stationary relative to the main frame of the press and the impression roller 20 and web tensioning roll 69 swing bodily with the assembly 13 relative to the stationary frame and the rolls 76 and 77 and relative to the printing cylinder 12. Any slack which develops in the web 21 between the roll 76 and the impression roller 20 due to upward rocking of the assembly 13 is taken up or compensated for by the roll 69 which moves with the assembly 13.

At each printing unit of the multi-color rotogravure press combined fluid pressure operated and spring means is provided to control the operation of the impression roller assembly 13 of such printing unit and to facilitate the quick separation of the impression roller from the printing cylinder at certain desirable times and also to provide for the controlled lifting of the impression roller well above the printing cylinder and for lowering the carrier bracket 14 into engagement with a positive stop or abutment to maintain exactly the desired contact pressure between the impression roller and printing cylinder.

This combined means for controlling each impression roller assembly 13 comprises a pair of diagonally inclined spaced parallel fluid operated cylinder-piston units 78, with each such unit arranged near and inwardly of the frame sides and 11, FIGURE 2, and spaced above the horizontal carrier bracket portion 15. Each cylinderpiston unit 78 has a pair of diametrically opposed trunnions 79, rockably journaled within openings of support brackets 80, in turn rigidly secured by bolt means 81 to the adjacent frame sides 10 and 11. Flexible hoses 82 and 83 are suitably connected in corresponding sides of the cylinders near the tops and bottoms thereof and above and below the pistons contained therein for conveying suitable pressurized fluid to or from the cylinders above or below the pistons therein. The pistons of the units 78 have axially downwardly extending piston rods 84 Whose lower ends are pivotally secured by pins 85 to rigid yokes 86 which in turn are rigidly secured by bolts 87 to the adjacent vertical edge of the horizontal carrier bracket portion 15, the yokes 86 projecting outwardly of such edge as shown in FIGURE 1. The yokes 86 and pins 85 therefore constitute an integral part of the rockable impression roller assembly 13 and which assembly is under direct control of the cylinder-piston units 78 as will be further explained.

Directly below the yokes 86 in axial alignment with the inclined cylinder-piston units 78 are compression spring units 88 having casings 89 rigidly secured by bolts 90 to the adjacent edges of the frame sides 10 and 11. Contained within each casing 89 is a relatively strong compression spring 91 having its upper end engaging a plunger 92 and constantly urging the same upwardly. Each plunger 92 has a top reduced extension 93 integral therewith for reciprocation through an opening in a top cap plate 94 of the spring casing. A hard metal plate or Washer 95 is rigidly mounted upon each cap plate 94 and likewise has an opening slidably receiving the plunger extension 93. The hard washer 95 provides a positive stop abutment surface for a coacting hard insert 96 on the lower inclined face of each yoke 86. That is to say, when the assembly 13 is in the position shown in FIG- URE l where the impression roller 20 is pressing the web 21 against the printing cylinder 12, the hard inserts 96 are in abutting relation to the hard washers or stop elements 95 and the assembly 13 can never swing below this position upon the axis of the pins 19.

Whenever the fluid pressure above the tops of the pistons in the units 78 is relieved by control means to be described or possibly due to a rupture of the hose 82 or the like, the springs 91 will instantly force the plungers 92 upwardly and the plunger extensions 93 will engage the bottoms of inserts 96 and slightly elevate the yokes 86 and the entire carrier bracket 14 about the axis of the pins 19. This will immediately slightly separate the impression roller 20 from the printing cylinder 12 as may be desirable when the press is stopped or for other reasons. When pressure is again established in the units 78 above the pistons therein, the springs 91 will yield and allow the inserts 96 to return to positive engagement with the stops 95 as where the impression rollers is under the full influence of maximum fluid pressure in the units 78.

FIGURE 6 shows schematically the pressure fluid control means for the cylinder-piston units 78 of a plurality of printings units of the rotogravure press. In FIGURE 6, two printing units and two pairs of cylinders and pistons are illustrated for the control of two impression roller assemblies 13, but it should be understood that the press may embody any practical number of multi-color printing units as is quite conventional.

As shown in FIGURE 6, a pump or compressor 97 for the system is provided to be driven by a motor 98. A main outlet line 99 for pressure fluid leads from the pump 97 to a main four-way control valve 101, actuated by a solenoid 102, and the valve 101 is common to all printing units of the press. A branch line 103 leads from the line 99 below the main valve 101 and connects to a pressure reducing device 104, also common to the several units of the press. The main valve 101 is connected by an output line 105 to a high pressure line 106, and the reducing device 104 is connected by an output line 107 to a low pressure line 108; said pressure lines 106 and 108 being common to the several units of the press, along with a common drain or return line 109 leading to an exhaust, reservoir or sump 110 and having a connection 111 with the main valve 101.

The high pressure line 106 is connected with each unit of the press by a respective branch line 112, 112, etc., a manually operable four-way valve 113, 113', etc., an output line 114, 114, etc., a pressure reducer 115, 115', etc., and a line 116, 116', etc., connected to the lines or hoses 82 which are in communication with the upper ends of the cylinders 78 of the respective units. The manual valve 113, 113 is also connected by a line 117, 117, etc. to the exhaust line 109. Similarly, the low pressure line 108 is connected with each unit of the press by a respective branch line 118, 118', etc., a manually operated four-way valve 119, 119', etc., and a line 120, 120', etc., connected to the lines or hoses 83 which are in communication with the lower ends of the cylinders 78 of the respective units. The manual valves 119, 119', etc. are also connected by lines 121, 121', etc. to the exhaust line 109.

FIGURE 6 illustrates the condition of the control systern for the press when the several impression roller assemblies 13 are being held slightly elevated from the printing cylinders under influence of the spring urged plungers 92 as where the press may be stopped or inactive. At this time, the main solenoid operated valve 101 is closed for blocking high pressure fluid from the line 99 to the common high pressure line 106 and to the tops of the cylinders 78. The relatively low pressure fluid passing from the reducing device 104 common to the several printing units is now also blocked from passage to the lower ends of the cylinders 78 by the low pressure manual valves 119 and 119 which are closed. The manual high pressure valves 113, 113, etc. may be open at this time but are ineffective to pass high pressure to the tops of the cylinders 78 since the main valve 101 is closed.

When it is desired to start the press and bring the several impression rollers into full printing or contact pressure with the underlying printing cylinders, the main solenoid operated valve 101 shifts to the open position and high pressure fluid from the line 99 is admitted to the common line 106 and through the individual valves 113, 113', etc and through the lines 116, 116', etc. to the.

tops of all of the cylinders 78, thereby forcing the pistons downwardly and applying high pressure to the tops of the same. All of the impression rollers are now forced into full printing contact with the printing cylinders and all units of the press may operate in the normal manner.

Should any diificulty be encountered at a particular unit of the press, such as foreign matter accumulating at the doctor blade with resulting smearing of the work, the high pressure manual valve 113, 113, etc. for that particular unit may be closed to block the passage of high pressure to the tops of the cylinders 78 for that unit.

When this occurs, the spring urged plungers 92 for that unit will instantly lift the impression roller out of contact a slight distance with the adjacent printing cylinder. The low pressure manual valve 119, 119', etc. for the same printing unit may now be opened to admit relatively low pressure to the bottoms of the cylinders 78 of that unit and this pressure will be suflicient to enable the pistons within the cylinders 78 to lift the dead weight of the particular impression roller assembly 13 to approximately the position shown in FIGURE 7. The operator may now clear the doctor blade or eliminate whatever ditficulty has been encountered at the one printing unit and when this has been done, such unit may be placed back into normal operation by again closing the manual valve 119, 119', etc. and opening the manual valve 113, 113', etc.

In like manner, while the main high pressure valve 101 is closed, any one of the low pressure manual valves 119, 119, etc. may be opened at any time to lift the dead weight of one or more of the impression roller assemblies 13 in the described manner.

Normally during the printing operation, full fluid pressure is introduced into the tops of the printing unit cylinders 78 as described above. However, under certain conditions, it is desirable to employ less than maximum printing pressure, and in such case the pressure reducers 115, 115', etc. may be selectively employed to somewhat reduce the fluid pressure being fed to the tops of the cylinders 78. When the pressure reducers 115, 115, etc. are thus employed, the operation of the remainder of the system is substantially the same as described above when full pressure is being employed.

Without a further description of the operation of the fluid pressure control system, it should now be fully apparent to those skilled in the art that the operation of the press is rendered highly flexible according to the invention and the impression roller assemblies 13 may be raised and lowered individually as required or raised and lowered in unison. The impression roller assemblies 13 may all, or individually, be slightly elevated instantly by the spring units 88 whenever the high pressure to the tops of the cylinders 73 is interrupted or relieved or whenever one of the hoses 82 or the like should fail. The procedure for elevating any selected one of the impression roller assemblies from its printing cylinder for cleaning the doctor blade or the like is highly economical and advantageous and much more desirable than shutting down the entire press and disturbing the position of the web and its tension throughout the entire press.

The pressure of the impression rollers 20 on the printing cylinders 12 may be finely adjusted throughout a wide range by manipulating the hand wheels 56 and 53 of the individual units in the manner previously described, and once the proper adjustment has been made in this respect, the positive stop means 9596 will assure a constant and uniform contact pressure between the impression rollers and printing cylinders throughout the continuous operation of the press.

Although a certain specific embodiment of the invention has been shown and described, it is obvious that many modifications thereof are possible. The invention, therefore, is not to be restricted except insofar as is necessitated by the prior art and by the spirit of the appended claims.

What is claimed is:

1. In a multi-color rotogravure printing press, supporting means, a printing cylinder journaled for rotation upon the supporting means, a carrier bracket arranged near the printing cylinder and pivoted to the supporting means and swingable in an arc toward and away from the print ing cylinder, an impression roller journaled upon the carrier bracket for rotation and bodily carried by the bracket and swingable therewith toward and away from the printing cylinder, fluid pressure operated means mounted on the supporting means and connected with the carrier bracket to swing the same toward and from the printing cylinder and to swing the impression roller between operative and inoperative positions with the latter giving access to said cylinder, and resilient means including a positive stop element secured to the supporting means in opposed relation to the fluid pressure operated means and engageable with the carrier bracket to limit the movement thereof toward the printing cylinder and operable to quickly shift the carrier bracket and impression roller a slight distance away from the printing cylinder whenever the fluid pressure operated means is inactive for urging said bracket toward or from said cylinder, whereby out-of-registry movement of said impression roll is reduced to a minimum except when work on said cylinder is required.

2. The invention as defined by claim 1, and a web tensioning roll bodily mounted upon the carrier bracket and spaced from and parallel to the impression roller, said tensioning roll be disposed laterally of said impression roller on the side toward the bracket pivot to swing laterally with said carrier bracket to maintain web tension when said bracket is swung to move the impression roller from said cylinder.

3. The invention as defined by claim 2, and means to adjust the web tensioning roll transversely of its longitudinal axis.

4. In a multi-color printing press, a printing unit, said unit comprising a pair of spaced upstanding frame sides, a printing cylinder journaled for rotation between said frame sides, pivot means extending inwardly from the frame sides on an axis spaced from and parallel to the axis of the printing cylinder, a carrier bracket arranged between the frame sides and rockably mounted upon said pivot means and disposed near one side of the printing cylinder and swingable toward and away from the printing cylinder about the axis of the pivot means, an impression roller journaled for rotation upon the carrier bracket and shiftable therewith toward and away from the printing cylinder, manually operable means on the carrier bracket and connected with the impression cylinder to adjust the opposite ends thereof separately or in unison toward and from the printing cylinder to thereby regnilate the contact pressure between the impression roller and cylinder and to align the impression roller with the printing cylinder, a web tensioning roll bodily mounted upon the carrier bracket and shiftable therewith and maintaining the web taut in all adjusted positions of the carrier bracket and impression roller, means to adjust the web tensioning roll transversely of its longitudinal axis, the web tensioning roll being substantially parallel to the axis of the impression roller, a pair of extensible and retractable fluid pressure operated devices arranged near opposite sides of the carrier bracket near the end thereof remote from said pivot means and pivotally secured to said frame sides and pivotally connected with the carrier bracket near said end thereof remote from the pivot means, control valve means for said fluid pressure operated devices to effect extension and retraction of the same and to hold said devices in selected adjusted positions, and positive stop spring devices secured to the frame sides in substantial axial alignment with the fluid pressure operated devices and in opposed relation thereto and engageable with the carrier bracket near said end thereof remote from the pivot means and serving to constantialy urge the carrier bracket and impression roller away from the printing cylinder and positively limiting movement of the carrier bracket and impression roller toward the printing cylinder.

5. The invention as defined by claim 4, and wherein said printing press comprises a plurality of said printing units, said units being identical in construction and operation, fluid pressure control means common to said units for operating said extensible and retractable fluid pressure operated devices thereof in unison, and separate fluid pressure control means individual to each unit of the press for operating said extensible and retractable fiuid pressure operated devices of each unit independently.

6. In a printing press, supporting frame means, a printing cylinder, a carrier bracket pivoted to the supporting frame means near one side of the printing cylinder and swingable toward and away from the cylinder, fluid pressure operated extensible and retractable means pivotally connected with the supporting frame means and carrier bracket and operable to swing the latter toward and away from said cylinder, a spring urged element on the supporting frame means in opposed relation to the fluid pressure operated means and engageable with the carrier bracket to urge the latter away from said cylinder, a positive stop abutment element on the supporting frame means engageable with the carrier bracket to positively limit movement thereof toward the cylinder, an impression roller mounted upon the carrier bracket for rotation and bodily movable therewith and parallel to the cylinder and adapted to engage the cylinder, said impression roller having a through shaft including shaft ends, bearings supporting the shaft ends and keyed thereto, jack screws secured to said bearings and extending transversely of said shaft ends, slides connected with said jack screws and spaced therefrom and parallel thereto, said carrier bracket having guide passages receiving said slides, tubular shafts journaled for rotation upon the carrier bracket and having screw-threaded engagement with the jack screws for effecting axial movement thereof, worm gears keyed to said tubular shafts for turning the same, a first shaft section journaled for rotation upon the carrier bracket at right angles to the jack screws, a first worm pinion secured to the first shaft section to turn therewith and meshing with one of said worm gears, a tubular shaft section engaging telescopically over the first shaft section and journaled for rotation thereon and upon the carrier bracket, a second worm pinion secured to the tubular shaft section and meshing with the other worm gear, a first hand wheel secured to the tubular shaft section for turning the same, a second hand wheel secured to the first shaft section for turning the same and being axially shiftable thereon, and releasable clutch means on the first and second hand wheels allowing the latter to rotate in unison with the first and tubular shaft sections when the clutch means is engaged or independently when the clutch means is disengaged to thereby facilitate shifting both ends or one end of the impression roller toward or from said cylinder to regulate printing pressure or to achieve parallelism between the impression roller and said cylinder.

7. In a printing press, supporting frame means, a printing cylinder, pivot means secured to the supporting frame means on an axis in spaced parallel relation to the axis of the printing cylinder, a generally L-shaped carrier bracket including an upper substantially horizontal portion overlying the printing cylinder and a depending generally vertical portion adjacent one side of the printing cylinder, said depending portion pivotally mounted upon said pivot means, an impression roller journaled dependingly upon the horizontal portion of the carrier bracket and between such portion and the printing cylinder and bodily swingable with the carrier bracket toward and from the printing cylinder, vertical jack screws mounted upon the horizontal portion of the carrier bracket and extending thereabove and connected with opposite ends of the impression roller to raise and lower such ends, gearing mounted upon the top of the horizontal portion of the carrier bracket and operable to raise and lower the jack screws in unison or independently to thereby adjust the contact pressure between the impression roller and printing cylinder, yokes secured to the end of said horizontal bracket portion remote from the pivot means and on the opposite side of the impression roller therefrom, diagonally inclined compression spring units including positive stop elements secured to the supporting frame means and adapted to abut said yokes when the carrier bracket is swung with the impression roller toward contact with the printing cylinder, and diagonally inclined fluid pressure operated extensible and retractable devices substantially aligned axially with said compression spring units and extending thereabove and above the carrier bracket and pivotally connected near their upper ends to the supporting frame means and pivotally connected near their lower ends with said yokes.

8. The invention as defined by claim 7, and wherein said compression spring units comprise casings secured to the supporting frame means, spring urged plungers within said casings and projecting thereabove and engageable with the bottoms of said yokes, the bottoms of said yokes disposed substantially at right angles to said plungers, and positive stop elements on the tops of said casings for abutting relation with the bottoms of said yokes.

9. The invention as defined by claim 8, and wherein said positive stop elements are hard metal plates having openings receiving said plungers, and hard metal inserts on the bottoms of said yokes adapted to abut said washers.

10. In a printing press, a support, a printing cylinder journaled on said support, an impression roll engageable with said cylinder to press a web to be printed thereagainst, a member movably mounted on said support and carrying said impression roll, positive stop means on said support and engageable with said member to limit movement of said impression roll toward said cylinder, double acting fluid pressure operated means connected between said member and said support for moving said member into engagement with said stop means and said impression roll into operative relation with said cylinder and also for moving said member from said stop means and said impression roll from said cylinder a distance suificient to provide access to said cylinder, and spring means between said stop means and said member for urging said member to move said impression roll a limited distance from said cylinder immediately upon release of pressure in said fluid pressure operated means, whereby outof-registry movement of said impression roll is reduced to a minimum except when work on said cylinder is required.

References Cited in the file of this patent UNITED STATES PATENTS 2,208,688 Stevens July 23, 1940 2,675,756 Vegell Apr. 20, 1954 3,027,831 Stapleford et a1. Apr. 3, 1962 

10. IN A PRINTING PRESS, A SUPPORT, A PRINTING CYLINDER JOURNALED ON SAID SUPPORT, AN IMPRESSION ROLL ENGAGEABLE WITH SAID CYLINDER TO PRESS A WEB TO BE PRINTED THEREAGAINST, A MEMBER MOVABLY MOUNTED ON SAID SUPPORT AND CARRYING SAID IMPRESSION ROLL, POSITIVE STOP MEANS ON SAID SUPPORT AND ENGAGEABLE WITH SAID MEMBER TO LIMIT MOVEMENT OF SAID IMPRESSION ROLL TOWARD SAID CYLINDER, DOUBLE ACTING FLUID PRESSURE OPERATED MEANS CONNECTED BETWEEN SAID MEMBER AND SAID SUPPORT FOR MOVING SAID MEMBER INTO ENGAGEMENT WITH SAID STOP MEANS AND SAID IMPRESSION ROLL INTO OPERATIVE RELATION WITH SAID CYLINDER AND ALSO FOR MOVING SAID MEMBER FROM SAID STOP MEANS AND SAID IMPRESSION ROLL FROM SAID CYLINDER A DISTANCE SUFFICIENT TO PROVIDE ACCESS TO SAID CYLINDER, AND SPRING MEANS BETWEEN SAID STOP MEANS AND SAID MEMBER FOR URGING SAID MEMBER TO MOVE SAID IMPRESSION ROLL A LIMITED DISTANCE FROM SAID CYLINDER IMMEDIATELY UPON RELEASE OF PRESSURE IN SAID FLUID PRESSURE OPERATED MEANS, WHEREBY OUTOF-REGISTRY MOVEMENT OF SAID IMPRESSION ROLL IS REDUCED TO A MINIMUM EXCEPT WHEN WORK ON SAID CYLINDER IS REQUIRED. 